The Biometrics Core (formerly the Biostatistics Core) provides the infrastructure that facilitates an organized, synergistic, and centralized approach to statistics in HIV/AIDS research at the University of Washington (UW) and the Fred Hutchinson Cancer Research Center (FHCRC). In particular, the Core provides advanced statistical methods and expertise in the design, conduct and analysis of clinical research and laboratory studies to CFAR investigators. The Biometrics Core also provides a crucial link between CFAR biomedical researchers and the large number of biostatistics and other quantitative sciences faculty at the University of Washington and the Fred Hutchinson Cancer Research Center who are developing new methods for HIV/AIDS research. The CFAR clinical, behavioral, and laboratory researchers using the Core provide datasets for analysis which motivate the development of new quantitative methods by biostatisticians, biomathematicians, engineers and computer scientists at UW and FHCRC. Hence, this link benefits CFAR investigators as well as academic quantitative science researchers. To promote and facilitate these multidisciplinary interactions the Biometrics Core: 1) provides statistical and mathematical collaboration and consultation on study design, forms design, evaluation and pre-testing, data analysis, interpretation and reporting; coordinates Data Safety and Monitoring Boards; provides data management services; maintains computing facilities that are available (both on site and by remote login) to any CFAR investigator; 2) sponsors and conducts training activities designed to disseminate statistical skills to CFAR investigators, inform the HIV/AIDS researchers about services available from the Biometrics Core, and introduce novel quantitative approaches to the UW/FHCRC CFAR community, 3) serves as a liaison between the Core user with advanced quantitative needs and experts from the UW Departments of Biostatistics, Statistics, Mathematics, and Applied Mathematics, and the FHCRC Program in Biostatistics and Biomathematics; 4) develops, adapts and/or implements new or novel statistical and mathematical methods as needed; and 5) organizes activities that promote communication among existing statisticians in HIV/AIDS research and interest from other biostatisticians that can be recruited to meet the growing demand of AIDS research.